An irony of how the events in Ukraine and the associated altercation with Russia have thrown many commentators and policy critics into a Cold War mode is that those same commentators and critics seem to have forgotten (or never learned) much relevant doctrine that was developed and honed during the real Cold War. The doctrine in question embraces many principles involving any attempt to exert power and to exercise influence over other states. The most relevant aspects of doctrine involve deterrence—using threats to dissuade someone from doing something we do not want done—as well as some related concepts also involving coercive methods of trying to influence an adversary's behavior.

Sophisticated treatment of these topics can become somewhat complicated, getting into such matters as multiple levels of deterrence and stability-instability paradoxes. But what much of the commentary on current issues ignores is really rather simple. It is stuff that should be apparent upon careful but straightforward thinking about the objectives, costs, and benefits that apply to the people on the other side of a conflict. Although applications of the principles have endless variations, the principles themselves are immutable. Probably what is still the clearest statement of them came during the height of the Cold War from Thomas Schelling, who received the Nobel memorial prize in economics largely for that work.

One major point of doctrine that has been routinely ignored in the recent commentary is that successful deterrence depends on much more than just the reputation of the deterring state and its demonstrated willingness to use coercion. It depends at least as much on characteristics of the particular conflict, including how much of a stake each side feels it has in it. We should have learned this lesson with the Vietnam War. The United States went so far in demonstrating its willingness to use costly force that it built up an army of over a half million in Vietnam and fought so long that it suffered over 50,000 combat deaths. But it was unable to deter the regime in the north from waging continued war in the south because the nationalist objective of uniting a Vietnam free of foreign domination was much more important to that regime than the United States's objectives in Vietnam were to it.

I have commented previously on the fallacious nature of the notion that for the United States not to take up a gauntlet in one conflict makes it more likely that some adversary in an unrelated conflict elsewhere on the globe would do aggressive things that it would not otherwise have done. Yet that notion persists, most recently in the assertion that Vladimir Putin would not have seized Crimea if the United States had only shown more toughness elsewhere. For many, of course, such an assertion is just one more disingenuous way for Barack Obama's political opponents to bash him. But the notion gets repeated so often that many who hear it, and at least some who say it, probably believe it.

This mistaken belief is related to another erroneous notion about deterrence, which is that taking coercive action against an adversary provides deterrence, rather than making such action conditional on the adversary doing certain carefully defined things we do not want him to do. Senator John McCain exhibited this mistake when he bemoaned how the modest steps the Europeans have taken in response to the situation in Ukraine would not deter Putin. He's right about that, but not because, as he further comments, commercial interests of the Europeans keep them from implementing harsher measures now. From exactly what are we trying to deter Putin? He says he has no intention of seizing any more of Ukraine after Crimea. We may have good reason to worry about the possibility that he might do so anyway, but he has not done so yet. Unconditionally imposing costs when he has not yet done so may satisfy political and other urges on our side, but it lacks deterrence value.

In some situations there may be a grain of truth, which can be found in Schelling's writings, in the idea that doing something forceful now can enhance deterrence against a future contingency, if the forceful action demonstrates a willingness to act in response to that particular contingency and there was reason to doubt that we would so act. But if there is not good reason for that doubt, again there is no deterrence value. The clearest recent instance of this fallacy was the failed attempt in the U.S. Congress to enact more anti-Iran sanctions legislation under the rationale that this would deter the Iranians from stalling or abandoning the negotiations. In fact, one of the least needed things to demonstrate to Tehran, given the now long history of overwhelming support in the Congress for serial enactment of sanctions against Iran, is a willingness to impose quickly still more sanctions if the Iranians did not negotiate seriously. There was disingenuousness here, too, in that much of the push for the legislation came from those who want negotiations with Iran to fail. But once again there were others who sincerely, but mistakenly, believed in the rationale.

A principle repeatedly ignored in American discourse is that in attempting to influence an adversary's behavior, getting him to believe he will not be punished if he behaves as we wish is just as important as getting him to believe that he will be punished if he does not so behave. This is true not only in situations of true deterrence, in which we want to prevent something from happening, but also in situations, for which Schelling created the term compellence, in which we want the other side to take action it is not currently taking. The principle is repeatedly ignored in discussions about the nuclear negotiations with Iran, in which a challenge much greater than convincing Iranians of American willingness to inflict more punishment is to convince them that punishment will end if they strike a deal satisfactory to us.

A similar deficiency in thinking has begun to infect the public discourse about Ukraine. Exactly what do we want from Putin at this point? Presumably it is more than just not invading eastern Ukraine, and includes positive, cooperative behavior in fashioning a settlement in which a Crimea-less but otherwise whole Ukraine can live in greater peace and prosperity and have positive relations with all its neighbors. What that behavior should be must be clear in our own minds and statements and thus clear in Putin's mind as well for any coercive or punitive action at this time to have compellent value.

Also too frequently ignored is attention to the costs of carrying out a threat—costs not just to the target of the threat, but to the side that would execute it. This attention is important not only to calculate costs and benefits if the threat ever did get carried out, but also because of how this affects credibility of the threat itself. If the other side does not believe the threat ever would be executed because doing so would be highly costly and damaging to the side making the threat, there again is no deterrent value. Such threats are worse than useless, because they risk exposing us as bluffers. Any show of military force by the United States in the vicinity of Ukraine (not the minor redeployments that merely provide some reassurance to Poland and the Baltic states) would exhibit this problem, given the patent folly for the United States to engage in a war with Russia, especially in Russia's backyard and especially given the much greater importance to Russia than to the United States of the distribution of power in this region.

Anyone guilty of exhibiting any of these mistaken ideas should take a refresher course in deterrence. If you yearn to be a Cold Warrior again, that should be one of the first things to do. Reading (or re-reading) Schelling would be a good way to fulfill that requirement.